global minus domination in graphs
نویسندگان
چکیده
a function $f:v(g)rightarrow {-1,0,1}$ is a {em minusdominating function} if for every vertex $vin v(g)$, $sum_{uinn[v]}f(u)ge 1$. a minus dominating function $f$ of $g$ is calleda {em global minus dominating function} if $f$ is also a minusdominating function of the complement $overline{g}$ of $g$. the{em global minus domination number} $gamma_{g}^-(g)$ of $g$ isdefined as $gamma_{g}^-(g)=min{sum_{vin v(g)} f(v)mid fmbox{ is a global minus dominating function of } g}$. in thispaper we initiate the study of global minus domination number ingraphs and we establish lower and upper bounds for the globalminus domination number.
منابع مشابه
Global minus Domination in Graphs
A function f : V (G) → {−1, 0, 1} is a minus dominating function if for every vertex v ∈ V (G), ∑ u∈N [v] f(u) ≥ 1. A minus dominating function f of G is called a global minus dominating function if f is also a minus dominating function of the complement G of G. The global minus domination number γ− g (G) of G is defined as γ − g (G) = min{ ∑ v∈V (G) f(v) | f is a global minus dominating functi...
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عنوان ژورنال:
transactions on combinatoricsناشر: university of isfahan
ISSN 2251-8657
دوره 3
شماره 2 2014
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